Automatic plug



.- I. Y .l I A Neu/Ibn fellenyer N ov. 18, 1930. N. c. SCHELLENGER1,781,958

AUTOMATIC PLUG l Filed Sept. 5, 1925 7 /f M///f Patented Nav. 1a, 1930UNITED STATES PATENT; OFFICE- NEWTON C. SCHELLENGEB, OF ELKHART,INDIANA, ASSIGNOR T CHICAGO TELEPHONE SUPPLY C0., OF ELKHART, INDIANA, ACORPORATION OI' DELAWARE AUTOMATIC PLUG Application led September Myinvention relates to telephone plugs of the type in which the terminalsor tips of the connecting cord may be readily connected or disconnectedbyV simple manual operatlons 5 not requirin tools. Such plugs arecommonly term automatic plugs.

According to my invention, I employ an automatically operating springclutch terminal or jack which is self-contained and compact. Such springclutch terminal or jack is shown and claimed per se in my copendingapplication, Serial No. 48,265, filed August 5 1925.

This clutch or jack is in the form of a cylindrical sleeve with aconcentric cylindrical sleeve release member projecting from the endthereof. That is to say, the release member is co-axial with the body ofthe clutch or jack and projects from the end thereof about the conductoror tip of the connectlng cord or wire.

Because of such shape the clutch terminals or jacks maybe disposed inparallel relation in an insulating handle giving a neat and compactdevice.

Also because of the self-contained character of the clutch elements, Iam able to make the handle of a sin le piece of insulating material ofvery simp e and inexpensive character easily produced, as, for example,from a block of fiber or easily moulded in a simple mould in a singlepiece.

In conjunction with the above, I employ a construction of plug contactssuch as disclosed in my copending application, Serial No. 24,002, tiledApril 18, 1925, which provides a self-contained cylindrical assemblywhich may also be disposed in the handle of the plug by a press fit in acylindrical hole in the plug handle.

Since the clutch terminals and the plug contact are self-contained andself-supporting, they may be connected by simple flexible 5, 1925.Serial No. 54,593.

threaded into the handle piece, but I find that close push fits aresuiiicient.

' The plug may have contact clutches or jacks for only one pair ofconductor tips or .for placing a plurality of receivers in series.

Now, in order to acquaint those skilled in the art with the manner ofconstructing and operating a device employing m invention, I shalldescribe in connection wit the accompanying drawings a specificembodiment of the same.

In the drawings Fig. 1 is a longitudinal section of an automatic plug ofmy invention;

Fig.` 2 is a front elevational view of same;

Fig. 3 is a longitudinal section of another embodiment which illustratesthe manner of constructing an automatic or more head sets or otherpleces of apparatus are to be connected thereto;

Fig. 4 is a longitudinal section of an embodiment similar to the oneShown in Fig. 3, but which is adapted to receive only one pair of cordtips; and

Fig. 5 is a sectional view of a jack which is more fully described inthe co-pending application above referred to.

In the preferred form of my automatic plug which I illustrate in Fig. 1,I employ a unitary housing or body member 1 which lug where one may beof liber, hard rubber, or what is commonly known and sold under thetrade name of bakelite. I preferably make this handle of liber becauseof its strength and cheapness. The housing 1 may be of any desired sizeor shape without departing from the spirit of the invention. It isprovided with a pair of substantially cylindrical openings oiset fromthe central arm at one end to receive the jacks 2 and 3, and a centrallydisposed opening at the opposite end to receive the sleeve 4. Theopenings for the jacks 2 and 3 and the sleeve 4 may be made by drillingthem in a suitable fixture in which the housing 1 may be secured. Or,the housing 1 may be moulded, in which case suitable cores could be usedso as to provide for the necessary openings.

The housing or handle is preferably made of a unitary piece ofinsulating material because this permits of a more neat and compactstructure, but I do not mtend to be .limited to a unitar housing as itobviously may be made up o separate parts.

The novel manner o securing the tip 5 to the sleeve 4 is more fullydescribed 1n my co-pending application on plug, Serial No. 24,002, filedApril 18, 1925, heretofore referred to. As shown, the tip 5 is threadedon a needle member 6 which is insulated from the sleeve 4 by means ofsuitable insulating Washers 7 and 8 at opposite ends of thesleeve. Itwill be noted that the op osite ends of the sleeve 4 are. counterbore toreceive the washers 7. By this construction, the need for a tubularinsulating member throughout the entire length of the sleeve iseliminated.

The opposite end of the needle 6 threads into a nut 9 under which thereis clamped one end of a flexible conductor 10. A similar flexibleconductor 11 is secured between the outer wall of the sleeve 4 .and theopening provided therefor in the'housing 1 by maklng the opening of suchsize that the sleeve 4 will have to be forced into the opening, when theconductor 11 is placed therein, by means of a press fit. The openin forthe jack members 2 and 3 are also o such size that the jacks may beforced therein by a press lit when the conductor members 10 and 11 areplaced therein. In this way the conductor 10 electrically connects thejack 2 with the tip 5 b means of the needle 6 and nut 9. Similarly, theconductor 11 electrically connects the jack 3 with the sleeve 4. Boththe conductors 10 and 11 are made of flexible conducting material,preferably a thin ribbon of braided copper. The ends of the conductorsmay be soldered to the respective parts if desired. The flexibleconductors may be made long enough so that they may be threaded throughthe block and soldered to the clutches and to the plug contacts andthereafter the clutches and plug may be forced into the holes, theconductors being merely folded or crumpled up inside the block. In suchcase the central;

parts of the conductors are insulated.

In the embodiment shown in Fig. 3, the housing 12, which is also aunit-ary structure, is also provided with suitable openings for thejacks 13, 14, 15 and 16 and the sleeve 17. All of these openings may beformed by suitable drilling operations, or by molding the member 12 andproviding suitable cores in the mold. The tip 18 is likewise secured tothe sleeve 17 b means of the needle 19 and the nut 20. uitableinsulating washers 21 and 22 at opposite ends of the sleeve serve toinsulate the sleeve from the needle and tip respectively. The sleeve 17is also adapted to be inserted into the opening provided therefor in thehousing 12 by means of -a press fit so as to hold the flexible oonductormember 23 firmly in contact with it. The ogposite end of the conductormember 23 is rmly held in contact with the outer wall of the jack 13 ina similar manner. The flexible conductor member 24 serves to electricallconnect the needle 19 with the outer wal of the jack 16. This member islikewise held in firm contact with the outer wall of the jack 16 bysecurin the jack in the opening provided for it in t e housing 12 bymeans of a press fit. A flexible conductor member 25 serves toelectrically connect the outer walls of the jacks 14 and 15 with eachother. To the outer surfaces of the jacks 13 and 16, adjacent thejacks14 and 15, are secured the spring members 26 and 27, respectively, bybein pressed in between the outer wall of the jacr and the inner wall ofthe housing. Each of the spring members 26 and 27 has secured to itinsulating discs or washers 28 and 29 in 'line with the openings in the'acli's or clutches 14 and 15 to be engaged y pin terminals which may beinserted in said jacks 14 and 15. A pair of contacts 30 and 31 aresecured to the outer walls or thimble portions of the jacks 14 and 15,and are normally in contact engagement with the spring members 26 and27. A sheet of thin fiber or other insulating material 32 serves toinsulate the jacks and the sp'ring members from the conductor 23.

The plug shown in Fig. 3 is particularly adapted for use in connectionwith tele hone head sets which are to be connected 1n series. When inuse, the tip members at the end of the flexible cord connection to thehead sets, are inserted in either the jacks 13 and 14, or the jacks 15and 16. If one head set is used and the cord tips are inserted in thejacks 13 and 1.4, the tip inserted into the jack 14 will bear againstthe insulating member or washer 28 and force the spring 26 out ofcontact with the contact member 30. In this way the cord tips in thejack 13 will be electrically connected to the sleeve member 17 The cordtip in the jack 14 will, on the other hand, be electrically connectedwith the tip 18. If it is desired to use another head set in series withthe one connected to the jacks 13 and 14, the cord tips thereof will beinserted in the jacks 15 and 16. By inserting one of the cord tips inthe jack 15, it will bear against the insulatin washer 29 secured to thespring member'2 and force the spring 27 out of contact with the contactmember 21. In this way, both head sets will be connected in series withthe sleeve -17 and the tip 18. Obviously, more than the two pairs of'acks illustrated in Fig. 3 may be used. is may be done by making thehousing 12 larger and, providing the number of openings therein equal tothe number of Jacks which are to be used. Each pair of jacks will have aspring member and a contact member adapted for engagement therewith forcutting t cuit. The conductor member 23 is, in each case, connected tothe jack farthest away from the sleeve 17. It will also be noted thatthe embodiment shown in Fig. 3 is not limited to havin the apparatusconnected to iacks connecte in series, as the connections between thejacks may be so arranged as to have the apparatus connected thereto inparallel and not in series.

Fig. 4 shows an embodiment of theinven tion which is similar to thatshown in Fig. 3,

except that it employs only one pair of jacks. In this embodiment, theunitary housing 35 is provided with suitable openings for the jacks 36and 37 and the sleeve 38. The jack 36 is connected electricall7 to thesleeve 38 by means of the flexible raided conductor 39, while the jack37 is electrically connected to the ti 40 at one end of the needle 41 bymeans o? a like conductor member 42 and the nut 43', which is adapted tosecure the conductor 42 irmly in contact with the needle 41. Suitableinsulating washers 43 and 44 prevent any possible contact between theneedle 41 and the sleeve 38. An insulating member 45 serves to preventany possible short circuit between the jacks -36 and 37 by the conductormember 39 when the acks are pressed into position' in the housin 35. y

The jack or clutchwhich is use in each of the embodiments described, isshown in section in Fig. 5. It comprises a thimble 50 in which ismounted for slidable engagement a releasing sleeve 51. A shackle elementor clutch member 52 serves to grip the cord tip which is shown in dottedlines and designated by the numeral 53, Aand also to hold it firmly incontact with the inner wall of the sleeve 51. The cord tip 53 may bereleased from the binding action of the element 52 b pressin down on thesleeve member 51 which uns ackles the pin terminal. It will be notedthat the end of the tip extends beyond tlie end of the thimble 50. Thisis done in order to permit the tip when used in plugs of the type shownin Fig. 3, to bear against the insulating members 28 and 29 so as tobring the standard members out of engagement with their cooperatingcontact members, but otherwise it is not necessary.

Due to the compact arrangement of the jack or clutch and its releasingelement, the terminals may be brought very close to each other withoutdanger of cross connection and without clamping the releasing elements.While the jacks or terminal clutches are shown as circular cylinders, itis to be understood that the shape may be varied without losing certainof the advantages of the present invention.

I do not wish to be limited to the details l5 shown or described.

e corresponding pair into cir- 1. In combination, a unitary housinghav,- imr a centrally disposed vopening and a pluraity of openingsoffset from the central axis thereof, a plug assembly ada ted formount-4 ing insaid centrall dispose opening, a plura ity of jack mem rshaving sleeves adapted for mounting in the offset openings of saidhousing, clutch means wholly enclosed within said sleeves and adapted toact independentl thereof, and means secured between the wal s of saidhousing and said sleeves for electrically connecting said jacks withsaid plug assembly.

2. In combination, an insulating housing having a plurality of openingsatithe front end -and a single opening at the back end, a sleeve securedwithin said single opening, a tip mounted on said sleeve and insulated4therefrom, a plurality of 'automatic jack members secured in the oenings at the front end of said housing, an flexible conductor meansconnecting said tip and sleeve with said jacks, said conductor meansbeing tightly embraced by said ]'acks 3, In combination, asingle unitarhousing having a plug opening and a jac opening, a plug assembly mountedin said plug opening, a jack member includin a sleeve adapted formounting in said jac vo ning e5 by means of a press lit, said jack mem rincluding clutch meansin said sleeve and operable independently of thehousing for gripping and releasing an electrical conductor, and meansfor connecting the jack to the plug including a flexible conductordisposed within the housing and having a portion positioned between saidsleeve and the wall of the 'ack opening, said ilexible conductor beingeld in place by said press fit.

4. In combination, a one-piece unitary housing having a plug opening anda plurality of jack openings, said housing having an intermediate o ningdisposed between and lconnecting sai plug and jack openings, 11o a plugin the plug opening and extending longitudinally from said housing,jacks mounted in said jack openings, said ]acks being disposed generallytransversely of the direction of extension of the plu from the housingand arranged side by side longitudinally of the housin and ex osedtrans-I versely through one si e of the ousing, and conductor meansdisposed in said intermedialte opening and connecting said plug and )acs.

5. In combination, a single unitary housing having a plug opening and aplurality of jack openlngs, said housing having an enlarged internalrecess disposed between the plug .and jack openings and connecting the]ack o enings with each other and each with said p ug opening, a plug inthe plug opening and extending longitudinally from said housing, jacksmounted in said jack openings independently of said plug, said jacksheilig disposed generally transversely of the direction of extension ofthe plug from the housing and arranged side by side longitu dinally ofthe housino` and exposed transversely through one side of the housing,and conductor means disposed in said intermediate opening and connectingsaid plug and jacks.

6. In combination, a housing having plug openings and a plurality ofjack openlngs, said housing having an intermediate opening disposedbetween and connecting said plug and jack openings, a plug in the` plugopening, jacks mounted in said jack openings, and conductor meansdisposed in said intermediate opening and connecting said plugand'jacks, said conductor means fitting and held in said jack openingsbetween the Wall of the housing surrounding said openings and theexternal peripheries of the jacks.

7. In combination, a single unitary housing having a central enlargedbore, ak plug opening extendin from one-side of said bore, a pluralityof 'ac openings extending from another side o said bore, a plug in theplug opening, jacks mounted in said jack openings, and conductor meansdisposed in said central enlarged bore for connecting said plug andjacks, said conductor means fitting and held in said jack openingsbetween the wall of the housing surrounding said openings and theexternal eripheries of the jacks. In witness whereo I hereunto subscribemy name this first day of September, 1925. NEWTON C. SCHELLEN GER.

